In every one of my dozen various & sundry .303's, I have found that 42.0 grs. of Alliant RL15 ahead of either a Hornady 174 gr. RNSP-IL seated to the cannelure and crimped or Sierra 180 gr. SPT bullets did the trick better than anything else I tried over the years.

My 202 gr. BRTORNFPGCTL Accurate Moulds Mould bullets like 28.0 gr. x2924 (BLC-2)